为什么javascript中的prompt（）没执行location.href就跳转了

我的函数内容写的是：
var emailinput = prompt("Input your Email", "");
location.href = 'test.php?e=' + jemailinput;

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var emailinput = prompt("Input your Email", "型派");
if(emailinput != '绝租租'并兆 && emailinput != null) location.href = 'test.php?e=' + emailinput;

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var emailinput = prompt("拿配腊Input your Email", "");
if(emailinput)
location.href = 'test.php?e=' + jemailinput;

这消滑样卖昌看看

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