PROC中的型別轉換

一、在c語言中:

(1)字元型到整型可用atoi() atol(),sscanf()

(2)整型,浮點型到字元型,可用sprintf()

(3)字元型到浮點型用atof()不行,最好用sscanf(),舉例如下:

exec sql begin declare section;

double d_demo;

float f_demo;

char ac_text[20]="222";

exec sql end declare section;

(1)sscanf(ac_text, "%f", &d_demo);

printf("ac_text=%s,d_demo=%f ",ac_text,d_demo);

(2)sscanf(ac_text, "%lf", &d_demo);

printf("ac_text=%s,d_demo=%f ",ac_text,d_demo);

(3)sscanf(ac_text, "%f", &d_demo);

printf("ac_text=%s,d_demo=%lf ",ac_text,d_demo);

(4)sscanf(ac_text, "%lf", &d_demo);

printf("ac_text=%s,d_demo=%lf ",ac_text,d_demo);

printf("******************* ");

(5)sscanf(ac_text, "%f", &f_demo);

printf("ac_text=%s,f_demo=%f ",ac_text,f_demo);

(6)sscanf(ac_text, "%lf", &f_demo);

printf("ac_text=%s,f_demo=%f ",ac_text,f_demo);

(7)sscanf(ac_text, "%f", &f_demo);

printf("ac_text=%s,f_demo=%lf ",ac_text,f_demo);

(8)sscanf(ac_text, "%lf", &f_demo);

printf("ac_text=%s,f_demo=%lf ",ac_text,f_demo);

輸出的結果:

ac_text=222.00,d_demo=0.000000

ac_text=222.00,d_demo=222.000000

ac_text=222.00,d_demo=222.000032

ac_text=222.00,d_demo=222.000000

*******************

ac_text=222.00,f_demo=222.000000

ac_text=222.00,f_demo=0.000000

ac_text=222.00,f_demo=222.000000

ac_text=222.00,f_demo=0.000000

d_demo=atof(ac_text);

printf("ac_text=%s,atof(ac_text)=%f ",ac_text,d_demo);

d_demo=atof(ac_text);

printf("ac_text=%s,atof(ac_text)=%lf ",ac_text,d_demo);

f_demo=atof(ac_text);

printf("ac_text=%s,atof(ac_text)=%f ",ac_text,f_demo);

f_demo=atof(ac_text);

printf("ac_text=%s,atof(ac_text)=%lf ",ac_text,f_demo);

輸出的結果:

ac_text=222.00,atof(ac_text)=1243288.000000

ac_text=222.00,atof(ac_text)=1243288.000000

ac_text=222.00,atof(ac_text)=1243288.000000

ac_text=222.00,atof(ac_text)=1243288.000000

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